engine GMC YUKON XL 2015 Service Manual

Black plate (39,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Instruments and Controls 5-39
STABILITRAK INITIALIZING
This message may come on if the
StabiliTrak system has not fully
initialized because of road
conditions or the incorrect tire size.
When the StabiliTrak system is fully
initialized, the message will turn off.
SeeTraction Control/Electronic
Stability Control on page 9-44. If this
message continues to be displayed
for multiple ignition cycles and on
different road surfaces, see your
dealer for service.
TRACTION CONTROL OFF
This message displays when the
traction control has been turned off.
See Traction Control/Electronic
Stability Control on page 9-44.
TRACTION CONTROL ON
This message displays when the
traction control is active. See
Traction Control/Electronic Stability
Control on page 9-44.
STABILITRAK OFF
This message displays when the
StabiliTrak system has been turned
off. Adjust your driving accordingly.
To limit wheel spin and realize the
full benefits of the stability
enhancement system, you should
normally leave StabiliTrak on. See
Traction Control/Electronic Stability
Control on page 9-44.
STABILITRAK OFF may also
display when the stability control
has been automatically disabled.
Several conditions can cause this
message to appear:
.If the system is overheating,
which could occur if StabiliTrak
activates continuously for an
extended period of time.
.If the brake system warning light
is on. See Brake System
Warning Light on page 5-22.
.If the stability system takes
longer than usual to complete its
diagnostic checks due to driving
conditions.
.If an engine or vehicle-related
problem has been detected and
the vehicle needs service. See
your dealer.
.If the transfer case is in
Four-Wheel Drive Low.
The message turns off as soon as
the conditions that caused the
message to be displayed are no
longer present.
Airbag System Messages
SERVICE AIRBAG
This message displays if there is a
problem with the airbag system.
Take the vehicle to your dealer for
service.
Security Messages
SERVICE THEFT DETERRENT
SYSTEM
This message displays when there
is a problem with the theft-deterrent
system. The vehicle may or may not
restart, so you may want to take the

Black plate (40,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
5-40 Instruments and Controls
vehicle to your dealer before turning
off the engine. SeeImmobilizer
Operation (Keyless Access) on
page 2-27 orImmobilizer Operation
(Key Access) on page 2-26.
Steering System
Messages
STEERING ASSIST IS
REDUCED DRIVE WITH CARE
This message may display if a
problem occurs with the electric
power steering system. If this
message appears, steering effort
may be slightly higher than normal.
The vehicle is still safe to drive. Use
caution while in reduced assist
mode. If this message is persistent
or appears repeatedly, take the
vehicle to your dealer for service.
See Steering on page 9-4.
SERVICE POWER STEERING
This message displays when there
is a problem with electric power
steering. Take the vehicle to your
dealer for service. See Steering on
page 9-4.
Tire Messages
SERVICE TIRE MONITOR
SYSTEM
If equipped with the Tire Pressure
Monitor System (TPMS), this
message displays if a part on the
system is not working properly. The
tire pressure light also flashes and
then remains on during the same
ignition cycle. See Tire Pressure
Light on page 5-25. Several
conditions may cause this message
to appear. See Tire Pressure
Monitor Operation on page 10-54.
If the warning comes on and stays
on, there may be a problem with the
TPMS. See your dealer.
TIRE LEARNING ACTIVE
If equipped with the Tire Pressure
Monitor System (TPMS), this
message displays when the system
is relearning the tire positions on
your vehicle. The tire positions must
be relearned after rotating the tires
or after replacing a tire or sensor.
See Tire Inspection on page 10-58,
Tire Rotation on page 10-58, Tire
Pressure Monitor System on
page 10-53, and Tire Pressure on
page 10-51.
TIRE PRESSURE LOW ADD
AIR TO TIRE
If equipped with the Tire Pressure
Monitor System (TPMS), this
message displays when the
pressure in one or more of the
vehicle's tires is low. This message
also displays with a vehicle picture
to indicate the location of the low
tire. The low tire pressure warning
light will also come on. See Tire
Pressure Light on page 5-25. You
can receive more than one tire
pressure message at a time. If a tire

Black plate (42,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
5-42 Instruments and Controls
message appears, stop as soon as
possible and turn off the vehicle.
Make sure the key is in the LOCK/
OFF position for at least
one minute, then restart the vehicle
and check for the message on the
DIC display. If the message is still
displayed or appears again when
you begin driving, the
four-wheel-drive system needs
service. See your dealer.
SHIFT DENIED
This message displays when the
shift lever is in M (Manual Mode)
and a transmission range has been
selected that is unavailable at the
current vehicle speed.
TO EXIT 4WD LOW SHIFT TO
NEUTRAL
If a four-wheel drive shift out of 4nis
requested, and the vehicle speed is
correct, but the transmission is not
in N (Neutral), this message will
display until the transmission is
shifted to N (Neutral).
TO EXIT 4WD LOW SLOW
TO XXX
If a four-wheel drive shift out of 4nis
requested, but the vehicle speed is
too high, this message will display
until the correct vehicle speed is
reached.
TRANSMISSION HOT IDLE
ENGINE
This message displays and a chime
may sound if the transmission fluid
in the vehicle gets hot. Driving with
the transmission fluid temperature
high can cause damage to the
vehicle. Stop the vehicle and let it
idle to allow the transmission to
cool. This message clears and the
chime stops when the fluid
temperature reaches a safe level.
When towing, use Tow/Haul Mode
to prevent damage to the engine or
transmission. See Tow/Haul Mode
on page 9-36.
VEHICLE IN 4WD LOW
This message will display if the
vehicle is driven in 4
nfor about
10 minutes above 72 km/h (45 mph).
Vehicle Reminder
Messages
CHECK TRAILER WIRING
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message may display and a
chime may sound when one of the
following conditions exists:
.A trailer with electric brakes
becomes disconnected from the
vehicle.
‐ If the disconnect occurs while
the vehicle is stopped, this
message clears itself after a
short time.
‐ If the disconnect occurs while
the vehicle is moving, this
message stays on until the
ignition is turned off.

Black plate (43,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Instruments and Controls 5-43
.There is a short in the wiring to
the electric trailer brakes.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull the vehicle over to the
side of the road and turn the ignition
off. Check the wiring connection to
the trailer and turn the ignition back
on. This message clears if the trailer
is reconnected. This message also
clears if you acknowledge it. If this
message still displays, either the
vehicle or the trailer needs service.
See your dealer.
See “Integrated Trailer Brake
Control System” underTowing
Equipment on page 9-82.
ICE POSSIBLE DRIVE
WITH CARE
This message displays when ice
conditions are possible.
TRAILER CONNECTED
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays briefly when
a trailer with electric or electric over
hydraulic brakes is first connected
to the vehicle.
This message clears itself after
several seconds. This message also
clears if you acknowledge it. After
this message clears, the TRAILER
GAIN and OUTPUT displays appear
in the DIC.
See Driver Information Center (DIC)
on page 5-28 and“Integrated Trailer
Brake Control System” under
Towing Equipment on page 9-82.
Washer Fluid Messages
WASHER FLUID LOW ADD
FLUID
This message displays when the
windshield washer fluid is low. Fill
the windshield washer fluid reservoir
as soon as possible. See Engine
Compartment Overview on
page 10-5 for the location of the
windshield washer fluid reservoir.
Also, see Washer Fluid on
page 10-20 for more information.

Black plate (4,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
6-4 Lighting
If the vehicle is started in a dark
garage, the automatic headlamp
system comes on immediately. If it
is light outside when the vehicle
leaves the garage, there is a slight
delay before the automatic
headlamp system changes to the
DRL. During that delay, the
instrument cluster may not be as
bright as usual. Make sure the
instrument panel brightness control
is in the full bright position. See
Instrument Panel Illumination
Control on page 6-6.
When it is bright enough outside,
the headlamps will turn off or may
change to Daytime Running
Lamps (DRL).
The automatic headlamp system
turns off when the exterior lamp
control is turned to
Oor the ignition
is off.
Lights On with Wipers
If the windshield wipers are
activated in daylight with the engine
on, and the exterior lamp control is in AUTO, the headlamps, parking
lamps, and other exterior lamps
come on. The transition time for the
lamps coming on varies based on
wiper speed. When the wipers are
not operating, these lamps turn off.
Move the exterior lamp control to
O
or;to disable this feature.
Hazard Warning Flashers
|(Hazard Warning Flashers):
Press this button to make the front
and rear turn signal lamps flash on
and off. Press again to turn the
flashers off.
When the hazard warning flashers
are on, the vehicle's turn signals will
not work.
Turn and Lane-Change
Signals
An arrow on the instrument cluster
flashes in the direction of the turn or
lane change.
Move the turn signal lever all the
way up or down to signal a turn.

Black plate (7,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Lighting 6-7
Pressmornnext to each reading
lamp to turn it on or off.
Lighting Features
Entry Lighting
The vehicle has an illuminated entry
feature.
When a door is opened, the dome
lamps and puddle lamps come on if
the dome lamp control is in the
DOOR position. If the dome lamp
control is in the OFF position, the
lamps do not come on.
The headlamps, parking lamps,
taillamps, and back-up lamps turn
on briefly at night, or in areas with
limited lighting, when
Kis pressed
on the Remote Keyless Entry (RKE)
transmitter. After about 30 seconds
the exterior lamps turn off. Entry
lighting can be disabled manually by
changing the ignition out of the OFF
position, or by pressing the RKE
transmitter
Qbutton.
This feature can be changed. See
“Vehicle Locator Lights” under
Vehicle Personalization on
page 5-44.
Exit Lighting
The headlamps, taillamps, parking
lamps, back-up lamps, license plate
lamps, and interior lamps come on
when the key is removed from the
ignition. The exterior lamps and
interior lamps remain on after the
door is closed for a set amount of
time, then automatically turn off.
If equipped with Keyless Access,
the exterior lamps automatically turn
on when a door is opened after the
ignition is turned off. The interior
lights turn on when the engine is
turned off.
The exterior lamps turn off
immediately by turning the exterior
lamp control off.
This feature can be changed. See
Vehicle Personalization on
page 5-44.

Black plate (8,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
6-8 Lighting
Battery Load
Management
The vehicle has Electric Power
Management (EPM), which
estimates the battery's temperature
and state of charge. It then adjusts
the voltage for best performance
and extended life of the battery.
When the battery's state of charge
is low, the voltage is raised slightly
to quickly bring the charge back up.
When the state of charge is high,
the voltage is lowered slightly to
prevent overcharging. The voltmeter
gauge or the voltage display on the
Driver Information Center (DIC),
if equipped, may show the voltage
moving up or down. This is normal.
If there is a problem, an alert will be
displayed.
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fastenough at idle to produce all the
power that is needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power, whenever
needed. It can temporarily reduce
the power demands of some
accessories.
Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommendedthat the driver reduce the electrical
loads as much as possible. See
Battery Voltage and Charging
Messages on page 5-31.
Battery Power Protection
This feature shuts off the dome and
reading lamps if they are left on for
more than 10 minutes when the
ignition is off. This will keep the
battery from running down.

Black plate (1,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Driving and Operating 9-1
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-3
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-3
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-4
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-5
Driving on Wet Roads . . . . . . . 9-10
Hill and Mountain Roads . . . . . 9-11
Winter Driving . . . . . . . . . . . . . . . 9-12
If the Vehicle Is Stuck . . . . . . . . 9-13
Vehicle Load Limits . . . . . . . . . . 9-14
Starting and Operating
New Vehicle Break-In . . . . . . . . 9-19
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 9-20
Ignition Positions (Key Access) . . . . . . . . . . . . . . . . . . . . 9-20
Ignition Positions (Keyless Access) . . . . . . . . . . . . . . . . . . . . 9-22 Starting the Engine . . . . . . . . . . 9-24
Engine Heater . . . . . . . . . . . . . . . 9-26
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-27
Shifting Into Park . . . . . . . . . . . . 9-28
Shifting out of Park . . . . . . . . . . 9-29
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . 9-30
Active Fuel Management
®. . . 9-30
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 9-30
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . 9-31
Automatic Transmission
Automatic Transmission . . . . . 9-31
Manual Mode . . . . . . . . . . . . . . . . 9-34
Tow/Haul Mode . . . . . . . . . . . . . . 9-36
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . 9-37
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . 9-41
Parking Brake . . . . . . . . . . . . . . . 9-42
Brake Assist . . . . . . . . . . . . . . . . . 9-43
Hill Start Assist (HSA) . . . . . . . 9-43
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . 9-44
Magnetic Ride Control . . . . . . . 9-46
Locking Rear Axle . . . . . . . . . . . 9-46
Automatic Level Control . . . . . 9-47
Cruise Control
Cruise Control . . . . . . . . . . . . . . . 9-47
Adaptive Cruise Control . . . . . 9-50
Driver Assistance Systems
Driver Assistance Systems . . . . . . . . . . . . . . . . . . . . 9-57
Assistance Systems for Parking or Backing . . . . . . . . . 9-58
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . 9-61
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 9-61
Active Emergency Braking System . . . . . . . . . . . . . . . . . . . . . 9-63
Side Blind Zone Alert (SBZA) . . . . . . . . . . . . . . . 9-65
Lane Change Alert (LCA) . . . . 9-66
Lane Departure Warning (LDW) . . . . . . . . . . . . . 9-68

Black plate (4,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
9-4 Driving and Operating
If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.
Steering
Electric Power Steering
This vehicle has electric power
steering. It does not have power
steering fluid. Regular maintenance
is not required.
If power steering assist is lost due
to a system malfunction, the vehicle
can be steered, but may require
increased effort.
See your dealer if there is a
problem.If the steering assist is used for an
extended period of time, power
assist may be reduced.
If the steering wheel is turned until it
reaches the end of its travel, and is
held in that position for an extended
period of time, power steering assist
may be reduced.
Normal use of the power steering
assist should return when the
system cools down.
See specific vehicle steering
messages under
Steering System
Messages on page 5-40. See your
dealer if there is a problem.
Curve Tips
.Take curves at a reasonable
speed.
.Reduce speed before entering a
curve.
.Maintain a reasonable steady
speed through the curve.
.Wait until the vehicle is out of
the curve before accelerating
gently into the straightaway.
Steering in Emergencies
.There are some situations when
steering around a problem may
be more effective than braking.
.Holding both sides of the
steering wheel allows you to turn
180 degrees without removing
a hand.
.Antilock Brake System (ABS)
allows steering while braking.
Off-Road Recovery

Black plate (6,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
9-6 Driving and Operating
One of the best ways for successful
off-road driving is to control the
speed.
{Warning
When driving off-road, bouncing
and quick changes in direction
can easily throw you out of
position. This could cause you to
lose control and crash. You and
your passengers should always
wear safety belts.
Before Driving Off-Road
.Have all necessary maintenance
and service work completed.
.Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped.
.Read all the information about
four-wheel-drive vehicles in this
manual.
.Know the local laws that apply to
off-road driving.To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam. However, driving without the
air dam reduces fuel economy.
{Caution
Operating the vehicle for
extended periods without the front
fascia lower air dam installed can
cause improper air flow to the
engine. Re-attach the front fascia
air dam after off-road driving.
Loading the Vehicle for
Off-Road Driving
{Warning
.Unsecured cargo on the load
floor can be tossed about
when driving over rough
terrain. You or your
(Continued)
Warning (Continued)
passengers can be struck by
flying objects. Secure the
cargo properly.
.Keep cargo in the cargo area
as far forward and as low as
possible. The heaviest things
should be on the floor,
forward of the rear axle.
.Heavy loads on the roof raise
the vehicle's center of gravity,
making it more likely to roll
over. You can be seriously or
fatally injured if the vehicle
rolls over. Put heavy loads
inside the cargo area, not on
the roof.
For more information about loading
the vehicle, see If the Vehicle Is
Stuck on page 9-13 andTires on
page 10-44.